1. Field of the Invention
This invention relates in general to an FM demodulator, and more particularly to an FM demodulator circuit and method that has a reduced sensitivity to noise which enhances the performance of a system.
2. Description of Related Art
Today's wireless communications markets are being driven by a multitude of user benefits. Products such as cellular phones, cordless phones, pagers, and the like have freed corporate and individual users from their desks and homes and are driving the demand for additional equipment and systems to increase their utility. As a result digital radio personal communications devices will play an increasingly important role in the overall communications infrastructure in the next decade.
Mixed-signal integration and power management have taken on added importance now that analog and mixed analog-digital ICs have become the fastest-growing segment of the semiconductor industry. Integration strategies for multimedia consoles, cellular telephones and battery-powered portables are being developed, as well as applications for less integrated but highly specialized building blocks that serve multiple markets. These building blocks include data converters, demodulators, filters, amplifiers and voltage regulators.
One important aspect of digital radio personal communications devices is the integration of the RF sections of transceivers. Compared to other types of integrated circuits, the level of integration in the RF sections of transceivers is still relatively low. Considerations of power dissipation, form factor, and cost dictate that the RF/IF portions of these devices evolve to higher levels of integration than is true at present. Nevertheless, there are some key barriers to realizing these higher levels of integration.
For example, most applications provide an FM demodulator in an RF receiver system to recover transmitted data from a carrier signal. For FM demodulators, robust performance requires a bit error rate (BER) performance close to the theoretical performance limit. However, this requires the implementation of circuitry which reduces the demodulator's sensitivity to noise.
It can be seen then that there is a need for an FM demodulator circuit method with reduced sensitivity to noise that provides a low bit error rate and performance.